In modern society, there is a series of accidents that takes place often. In developed societies, accidents related to car traffic are one of the main causes of death. Likewise, many people who make it to survive those traffic accidents partially or fully lose their body motility control due to the injuries resulting from the abovementioned traffic events.
In addition to accidents, whether they are car traffic ones or not, there are other causes resulting in the loss of voluntarily moving some part of one's body. Such causes may be an illness or injury at any points along the motor nerve system between the brain and the muscle fibers, which may arise from injury, poisoning, infection, hemorrhage, occlusion of blood vessels, or tumors, where paralysis may be temporary or permanent.
Temporary paralysis, also known as paresis, often results from infections, traumas, or toxic substances which suppress for a while the motor activity, but do not result in serious injury of nerve cells. On the other hand, permanent paralysis results from extended injury in nerve cells or a nerve root, where nerve cells being seriously injured cannot regenerate. Paralysis of one limb is called monoplegia; paralysis of both limbs at the same side is called hemiplegia; paralysis of both lower limbs is called paraplegia or diplegia; and paralysis of the four limbs is called quadriplegia or tetraplegia.
The United States is known to have a total of about 250,000 permanent quadriplegic patients and its number increases at a rate of 10,000 cases per year. Likewise, according to data from the last general population census, Mexico has about 814,000 people having problems of motor disability.
The immovability of quadriplegic patients makes them to be most of the time laying on a bed and they are thus at risk of developing eschars and sores on their skin, since their immovability prevents them from moving their body and place them in a different position as often as normal people may do so. In this sense, the best to avoid the appearance of eschars and sores is to change the position of the patient in bed, in particular to initially place the patient lying on his back and then turn the patient face down and alternately changing the patient position in periods of time of at least four hours. An important aspect to be considered in this 180° position change is the safety that must be kept to avoid generating additional injuries to the patient.
Thus, in the state of the art, therapeutic beds have been developed to provide such a position change, such as the one depicted in the International Patent Application No. PCT/IE96/00087, published under number WO 97/22323, which depicts a therapeutic bed comprising a support-frame with wheels and a Trendelenburg position support-frame (where feet are located in a plane more elevated than the head) including curved arms that are mounted on guide wheels of the support-frame with wheels. The Trendelenburg position support frame has also guide wheels on which there are rings located in opposing ends of the bed. Likewise, a patient support platform is mounted on the rings, such platform including a mattress and leg supports. Furthermore, the bed includes side rails that are engaged and fastened to the patient support platform. Every side rail incorporates support means for the patient laying face down, the means comprising a head support, an adjustable abdomen support, and sections of support cushions which are longitudinally separated to define adjustable support parts that are mounted so that they can move as a hinge or blade, be engaged, and fastened.
The therapeutic bed provides the patient with a position in which he lies face down by means of the 180° rotation of the rings mounted on the guide wheels. Likewise, the bed may be used for kinetic therapy and/or Trendelenburg movement when a patient is laying face down.
This bed has a quite complicated design, since one of its objects is to be used in the treatment of patients having respiratory problems, being thus only used in hospitals and being operated exclusively by qualified personnel, which is a disadvantage when the bed is used for quadriplegic patients who, most of the times, are at their own home and are directly taken after by their relatives. Therefore, there is a need for beds having a simpler operation and construction which, however, are also provided with safety systems allowing to perform the patient 180° position change in a safely manner.
In particular, it is desirable to have beds where none of the patient limbs are hanging or protruding form the bed when performing the patient position change. Furthermore, beds must not have protuberances or projections that may prove dangerous when the patient position is changed. These are very important aspects to be considered when selecting a bed for quadriplegic patients or patients suffering from motor disability problems.
On the other hand, when a person is suspected to have an injury in the backbone and/or spinal cord, the patient is immobilized and subjected to a therapy known as cervical traction, which aims to keep the patient backbone straight. For that purpose, the patient's head is horizontally pulled by using a free weight hanging from the bed and, in particular, a diadem is placed on the patient and a string is attached to it, whose other end has a free weight which hangs from it. The cervical traction is also a recovery therapy applied in several cases (vertebral listhesis).
For the cases mentioned in the preceding paragraph, it is desirable that the patient position change is performed in a safely manner without ceasing to apply the cervical traction to it. It is worth mentioning that the bed depicted in document WO 97/22323 does not mentioned any means by which the cervical traction therapy may be performed.
Likewise, the operation of the previously depicted bed may represent a complex task for one person alone, since it is necessary to make a considerable effort to place on the patient the cushions which support him in a position in which he lies face down and which are adjusted and secured by using strings to rotate then the rings allowing to perform the 180° rotation.
Regarding the above, it is important bearing in mind the fact that the patient is laying face down and supported only by the cushions, which do not provide a support such as firm as when the patient is laying on his back and is supported by the platform. Furthermore, the safety of the patient laying face down may be reduced in this bed if the strings had not been properly stretched.
Another disadvantage that may be found in the bed depicted in the International Application No. PCT/IE96/00087 is the one related to the limited access to the patient when he is laying face down. In particular, with such bed there is only access to the patient's back when he is in such a position, since the support platform makes the access to the patient difficult, since it is securely fixed on the rings. In this sense, it is desirable to have an easy, rapid, and total access to the patient body when he is laying face down and even on his back. A total access facilitates taking care of the quadriplegic patients or patients suffering from motor disability.
On the other hand, in the prior art there is the bed depicted in the Patent International Application No. PCT/IE99/00049, published under number WO 99/62454, which shows improvements with respect to the bed depicted in International Publication No. WO 97/22323, such improvements being mainly focused to two issues, namely: 1) providing means for care lines directed to patients suffering from severe respiratory problems; and 2) providing the safety needed to rotate the patient.
Regarding the bed depicted in the Application No. PCT/IE99/00049, it can be mentioned that such a bed is to be used mainly in hospitals and, furthermore, it continues to show problems with respect to the limited access to patients when they are laying face down. In spite that the patient support platform provides panels that can be moved as a hinge or blade on a transversal central bar included in the platform to have access to the patient, such an access is partial and only towards the patient's back. Regarding safety, the bed of such a document provides in particular retention means to detachably fastening a patient to the support platform, such support means being operatively attached to the actuating means ruling the rotation of the patient support platform so that, if the retention means are in a proper position, the rotation is allowed. In order to achieve the above, the document mentions the inclusion of sensor in the clasps and strings indicating if the parts have been properly coupled.
Finally, in the state of the art there is a bed depicted in the US Patent Application Serial No. US 2002/0138906 A1, which is extremely similar to that described in the Application No. PCT/IE99/000049. The bed depicted in such US application incorporates improvements related to providing at the rotating rings a section that may be disassembled, sensors indicating if the strings are stretched enough, as well as providing side rails facilitating the access to the patient. In other words, such a document improves in certain aspects the functionality of the bed. However, it continues to have a design that it is mainly directed to be used in hospitals.
The bed depicted in the US Patent Application Serial No. US 2002/0138906 A1 more particularly comprises: A base frame, a platform to support the patient which is rotationally mounted on the base frame for a rotational movement around a longitudinal axis, an actuating system to rotate the patient support platform on the base frame, an end ring straightened up at the bed head board having a central opening to carry lines to take care of the patient, and a removable upper section to improve access to the patient's head. The patient support platform preferably has rotationally mounted side rails which are bent under the patient bed, as well as strings with string connectors indicating if the strings are stretched enough. A direct wired electric connection between the patient support platform and the base frame allows the full rotation of the patient in any direction. Furthermore, it includes a lever manually operated which disengages the patient platform from the actuating system to allow the manual rotation of the patient platform.
According to the above, in such a bed the patient is supported by a series of cushions that are fastened by means of strings incorporating sensors to indicate if such strings are stretched enough. However, as any electromagnetic device, there is the risk for failures in sensors, which would result in a full failure of the safety system.
As it may be seen, the beds depicted in the three abovementioned documents share a very similar structure, which is complex and bulky, mainly because the base with wheels is basically formed by a horizontal rectangular frame provided with various elements in order to provide the “Trendeleburg” position and provide support to the guide rings and, furthermore, the rings mounted at the bed head and foot are also very bulky.
In this sense, it is appropriate that a bed for these patients is not very bulky and, furthermore, that it may be easily assembled and disassembled by one single person, although the beds from the previous art do not consider any of these features. A bed having elements that can be easily disassembled would provide countless advantages to these patients, mainly regarding their relocation and hygiene. More particularly, it is appropriate that the platform providing support to the patient is rapidly removed from the bed and relocate the patient on it. However, the beds from the previous art do not allow this possibility.
Furthermore, it is desirable to have a bed not only allowing the patient to rotate, but providing also the patient with comfort. In particular, beds must be adjustable for height and inclination (Trendelenburg position), have an adjustable tilted back support in order for the patient to seat and have food, and it must be designed in order to conduct lines to provide saline solution to the patient or lines for providing other medical care, without these lines interfering with the operation of rotating the patient.
Moreover, it is desirable to have a bed in which various devices may be used, such as bedpans in order for the patient to evacuate. Considering that the patient is laying face down for long periods of time, the bed must have a window or space which represents no obstruction of the patient's visual field, in order for him to be able to read books or watch television screens.
Another important issue in these beds is that the lowest possible force is needed to change the patient position by a 180° turn, while in the beds from the previous art such a turn was achieved by means of electric motors. However, as it has been mentioned in this chapter, it is desirable to have a bed where one single person may be able to perform the turn and, furthermore, without the need of using electric motors. The above is considering that this rotation operation is a repetitive one.
Likewise, another disadvantage of the beds from the previous art is that, since they include electric or electromagnetic components, they cannot be in contact with water and thus patients need to be relocated in other devices for bath. It is therefore desirable to have a bed in which patients may have a bath on the bed itself.
As it may also be seen, the beds from the previous art, due to their design and use in hospitals, are considerably expensive and they are thus not affordable by families of developing countries, such as Mexico, where an important percentage of the population has low income and quadriplegic relatives.
Consequently, the disadvantages from therapeutic beds in the state of the art have been pretended to be overcome by developing a therapeutic rotationally bed having an extremely simple and economical construction, but having a design allowing a person to change the patient position by means of a 180° turn of the patient in an easy but above all safe fashion. The bed from the present invention eliminates the use of strings to fasten the patient when he is laying face down. However, for this position, it provides a firm support, such as when the patient is laying on his back. The bed of the present invention is integrated by elements which can be rapidly disassembled and facilitate a full access to the patient when he is laying on his back or face down, so that he is able to be provided with all the needed care. Likewise, the bed of the present invention has a not very bulky base allowing its movement through narrow corridors and, above all, it has a design allowing it to be used at home, as well as in hospitals. The inner part of the base has means allowing the provision of the Trendelenburg position.